Effects of Administering Prophylactic Acetaminophen on Short‑term Complications of Vaccination in 6‑month‑old Infants

Background: We aimed to assess the effects of administering prophylactic acetaminophen on short‑term complications of vaccination in 6‑month‑old infants admitted to a private pediatric clinic in Rasht (Iran) during 2002–2013. Methods: This quasi‑experimental study was conducted on 696, infants aged 6-month-old admitted to a pediatric clinic in Rasht before vaccination during 2002–2013. Overall, 31 infants were excluded during the course of the study. While prophylactic acetaminophen was administered in 322 participants (intervention group), 343 infants (control group) received acetaminophen after vaccination. Data were collected by a checklist including complications such as fever, drowsiness, anorexia, seizure, long and excessive crying, mood change, pain, and wound at the site of injection, abscess, induration, limb swelling, and erythema. The time of occurrence of each complication was also recorded. Data were analyzed by Chi‑square test in SPSS 16.0. P < 0.05 was considered significant. Results: Six hundred sixty‑five participants (49.6% boy) were assessed in this study. The intervention and control groups had no significant difference in terms of sex distribution (P = 0.53). Short‑term complications occurred in 45% of the infants. The most common complications were erythema (24.4%), induration (19.9%), and low‑grade fever (16.1%). There was a significant relation between administering prophylactic acetaminophen and the incidence of low‑grade fever (P=0.01), induration (P = 0.01), and anorexia (P = 0.03). Conclusions: Our findings indicated the efficacy of prophylactic acetaminophen in reducing postvaccination complications in a population of Iranian infants. According to our findings, further research is required to determine the preferred dose and time of administering acetaminophen.